Chronic Mountain
Sickness

Zubieta-Castillo, G. and Zubieta-Calleja, G.

HIGH ALTITUDE PATHOLOGY INSTITUTE (IPPA). La Paz, BOLIVIA

The capacity of adaptation of human beings to atmospheric pressure
changes is noteworthy. In high altitude adaptation (HAA) we should consider:
that of normal man and that of the diseased. The acute HAA can be more
dramatic and dangerous than chronic HAA. In order to increase the oxygen
carrying capacity of blood at high altitude, the number of red blood cells
increase (as initially described by the French physiologist Viault) in
normal high altitude residents. This increase is greater in some cases
of cardiac or respiratory disease at high altitude, in what has been called
chronic mountain sickness by the Peruvian scientist Carlos Monge. This
abnormal increase is also called increased polycythemia or excessive erythrocytosis.

Disease at high altitude is the same as that at sea level but with
HYPOXIC PHYSIOGNOMIES. In the Bolivian Andes above 3000 m, respiratory
disease with INCREASED POLYCYTHEMIA affects thousands of patients. With
the availability of pulmonary function tests and blood gas techniques,
it is increasingly evident that CMS is due to some ventilatory or respiratory
alteration-*+.